RESEARCH EVALUATING VAGAL EXCITATION AND ANATOMICAL LINKS

Duty cycle: At Visit 1, while the frequencies are being changed over Period 1, 2, and 3, duty cycle will be held constant at the participant's randomly assigned first duty cycle setting. At Visit 2, duty cycle will be held constant at the participant's randomly assigned second duty cycle setting. At Visit 2 the participant will receive whichever duty cycle they were not randomly assigned at Visit 1. Therefore, by completing the combination of three frequencies at two duty cycles, each participant will have received all six possible VNS parameter combinations over the two study visits. Chronic period: The VNS setting for the Chronic Period in between Visit 1 and Visit 2 will be the same settings as tested during Visit 1 Period 3. Since Visit 1 Period 3 settings were already randomly assigned to each participant, another randomization for the chronic period is not needed.